csppfetch.Downloader.DownloadStatistics exists

It's just an alias of csppfetch.DownloadStatistics.

It's a convenience, so if another module handed you a Downloader, you
can eaisly get the DownloadStatistics without personally needing to
import csppfetch

csppfetch/__init__.py

@@ -373,6 +373,9 @@ class Downloader:
     """ Knowledge of how to download a given data source's files
     """
 
+    # This is just a convenience for users of a Downloader object
+    DownloadStatistics = DownloadStatistics
+
     def __init__(self,
             name,
             package_env_id,